Decorative article and method of making same

ABSTRACT

A decorative article and method of making same is disclosed wherein pictures are printed in a contrasting color on substrates such as ceramic, glass and the like.

United States Patent Hager et a1. 1 51 Dec. 9, 1975 [5 DECORATIVEARTICLE AND METHOD OF 3,622,322 9/1968 B1111 96/38.1 MAKING SAME3,669,665 6/1972 Faigerlbaum et a]. 96/35 3.674.492 7/1972 Goldriek6161 1. 96/383 1 Inventors: Rlchard gfl; Frans C- 3,754,913 8/1973TflkfiUChi et a1 96/36 H er both of 1464 Wess x A 25 Aims, Cam 94022 e WFOREIGN PATENTS OR APPLICATIONS 9 Fflfidz J n 1 19 2 1,371,253 6/1963France 6/35 [2]] Appl NO: 263,684 OTHER PUBLICATIONS Rose et 211., TheCondensed Chemical Dictionary, Sevd' 1' 1966. 152 1.1.s.c1. 96/38.l;96/35; 96/36; E Remhold Pub Corp 96/383; 427/248; 427/255; 428/432; P GF Le 428/433; 428/434; 428/469 "'T gorge .Smes 2 Ass/slantExammerStanley S. SIlverman [51] Int. Cl. G03C 5/00 h b h& [58] Field 61Search 96/27 R, 36, 35, 38.1, g mbac ac [56] References Cited [57]ABSTRACT UNITED STATES PATENTS A decorative article and method of makingsame is 3,317,318 S/1967 Backus et a1. 96/331 disclosed wherein picturesare printed in a contrasting 3,415,648 12/1968 Cerla 915/36 color onsubstrates such as ceramic, glass and the like. 3,488,194 1/1970 Lydick6161.. 96/383 3,573,908 4/1971 121111116111 96/34 7 Claims, 5 DrawingFigures SUBSTRATE MATERIAL PREPARATIONS CLEANING 0F SUBSTRATES PR1NT1NG0F SUBSTRATES EXPOSE PHOTORESIST I L 111112101 PHOTORESIST 1 @151 BAKE1110101115151 US. Patent Dec. 9, 1975 FIG.I

FIG.2

Sheet 1 0f 2 SUBSTRATE MATERIAL PREPARATIONS CLEANING OF SUBSTRATESLOADING OF VACUUM CHAMBERS THIN FILM DEPOSITION UNLOADING OF SUBSTRATESCOATING (SPIN COATING) WITH PHOTORESIST PREBAKE 0F PHOTORESIST STORAGEOR PACKING IN LIGHT TIGHT PACKAGE PRINTINGOF SUBSTRATES EXPOSEPHOTORESIST DEVELOP PHOTORESIST POST BAKE PHOTORESIST Emu momma BISMUTHOXIDE OPTION REMOVE PHOTORESIST BAKE OUT BISMUTH OXIDE OPTIONALPROTECTION COATING OR GLAZED SURFACE BAKE OUT BISMUTH OXIDE ANDPHOTORESIST OPTIONAL PROTECTION COATING OR GLAZED SURFACE U.S. PatentDec. 9, 1975 Sheet 2 of2 3,925,079

FIG.3 u

F I G 5 Fl G .4

DECORATIVE ARTICLE AND METHOD OF MAKING SAME BACKGROUND OF INVENTIONThis invention is directed in general to a decorative article and methodof making same in the form of a picture in a contrasting color printedon a substrate such as ceramic, glass etc. The article provides aconsumer product as jewelry, ornaments and the like.

The conventional way of decorating consumer type ceramics, porcelain andglasses is by printing, brush painting or silk screening of patterns onthe substrates or materials. After the pattern has been established, thework is usually glazed by firing it in a kiln and the product isfinished. Often times the printing or painting is painstakingly done byhand or the master silk screen is produced by hand resulting in a veryexpensive product. Usually, the cost is prohibitive where a singlearticle with a unique pattern or print is desired. Also there is a needfor a consumer product where the prints are produced with much moreprecision than presently commercially available and yet still madeavailable at a price competitive with decorative ceramics, porcelain andchinaware.

The object of the present invention is to provide a decorative articleand method for making same for producing pictures on substrates incontrasting color and utilizing photographic techniques. As used hereincontrasting color" or color" is used to include achromatic colors suchas black, white and grays as well as chromatic colors.

In accordance with one aspect of the present invention the decorativearticle is provided by first layering the substrate with an imageforming material that will result in a color contrast picture on thesubstrate and then coating the layered substrate with a photosensitivematerial. The photosensitive material is exposed with a picture which isdeveloped to then provide a mask for removing undesired image formingmaterial defined by the picture leaving a contrasting color picture ofimage forming material on the substrate.

The substrate materials which have been used are ceramics, sapphire,glass, gold and metal-coated, such as gold-coated, ceramics.

Good image forming materials are bismuth oxides such as bismuthtrioxides of the yellow rhombic, white rhombic and gray-black cubiccrystalline forms. A highly desirable combination is bismuth trioxide ofthe gray-black cubic form on a ceramic (alumina) substrate producing ahighly desirable black on white article.

Since photographic techniques are utilized to form the picture on thesubstrate, the article can be formed quickly and easily by unskilledlabor thereby producing an economical consumer product. Also by usingphotographic techniques, a precisely defined picture can be reproducedon the substrate.

Other colors or color combinations are possible with selected material.Bismuth oxide then can be coated on or coated by gold, silver orplatinum. Similarly, by variations in the manufacturing techniques,color differences can be produced using the same materials.

These and other features and advantages will become more apparent upon aperusal of the following specification taken in conjunction with theaccompanying drawings wherein similar characters of reference refer tosimilar structures in each of the several views.

FIG. 1 is an enlarged perspective view of an article produced inaccordance with the present invention.

FIG. 2 is a block diagram flow chart showing the steps performed withthe present invention.

FIG. 3 is an enlarged sectional view through an article prepared forprinting in accordance with the left hand side of FIG. 2.

FIG. 4 is an elevational view schematically illustrating one simpletechnique for contact printing the picture onto the substrate.

FIG. 5 is a top view of a slide projector illustrating slide projectionillumination of a decorative article pro duced in accordance with thepresent invention.

While the present invention has many applications to articles ofdifferent sizes, shapes and materials for substrates and many differentcoating materials, a unique black and white decorative article isproduced with the present invention and will be described as a preferredembodiment.

Referring now to the drawing there is shown in FIG. I an article 11 suchas a small piece ofjewelry as a cuff link or tie tack provided with aprinted picture thereon. In the embodiment illustrated the substrate orwhite material on which the picture is printed is alumina and the blackportions of the picture are formed of bismuth oxide, specificallybismuth trioxide of the gray-black cubic crystalline form. Bismuth oxideis used herein to describedany of the oxides of bismuth and as moreparticularly defined. Bismuth trioxide is a suitable material and hasseveral crystalline forms, yellow rhombic crystalline form having amelting point of 820C, white rhombic crystalline form having a meltingpoint of 860C, and gray-black cubic crystalline form having a transitionpoint of 704C. It is possible to start with any one of these crystallineforms and by proper evaporation end up with a desired final coating. Asanother alternative material, bismuth pentoxide of the dark red or browncrystalline form can be utilized.

Referring to FIG. 2, the method for forming the article 11 includesfirst cleaning the alumina substrate and loading the substrates in avacuum evaporation chamber of any of the commercially available typesfor vacuum evaporation at a level of approximately 10' torr level orbetter. A thin layer of bismuth trioxide of the gray-black cubiccrystalline form can be produced by starting with bismuth trioxide whiterhombic crystalline form powder placed in an alumina coated boat in thevacuum. With proper evaporation temperature and rate, the deposit on thesubstrate will end up with the cubic black crystalline structure. Thisblack coating provides good black prints and adheres well to whiteceramics (for black and white prints), on gold or gold coated substrates(black on gold prints) and black on other colors depending upon thecolor of the substrates. Bismuth oxide adheres well to ceramics,sapphire and glass as well as metals such as gold, silver and platinum,which can be provided in a desired pattern on one of the aforementionedsubstrates. It is also possible to coat the gold, silver or platinum onthe bismuth oxide for a gold, silver or platinum picture on black.

With different evaporation temperatures and rates and different boatmate rials such as tantalum, tungstem and molybdenum it is possible toobtain depositions of bismuth oxide in colors from black to red-brown.After vapor deposition in thicknesses of typically between 0.4 and 1micron the vacuum in the chamber is broken and the coated substratesunloaded.

Next, the bismuth oxide surface is coated with an appropriatephotoresist material for defining the picture on the article. Where thepicture is formed from a photo negative, a negative type photoresistmaterial is appropriate or where a slide is utilized, a positive typephotoresist material is utilized, The photoresist mate rial can beapplied in one of the well known techniques such as dipping, spraying orspinning. For sharp, fine prints spin coating works very well. Thephotoresist is prebaked in place and then the substrates are packaged ina light tight manner for storage or shipment to the customer who willprint upon them.

FIG. 3 shows an enlarged elevational sectional view taken through one ofthe prepared substrates showing the alumina substrate provided with thedark, thin film coating 16 of bismuth trioxide which is in turn coatedwith the photoresist coating 17.

For printing the picture on the prepared substrates a standard photonegative, slide or glass mask for contact printing or productionprinting can be used, and normal photo exposure procedures are thenfollowed.

An economical way of printing is the use of a standard slide projector21 as shown in FIG. 4 and wherein the projection light beam is directedby an angled mirror 22 onto the photo negative 23 positioned in contactwith and on top of the photo-resist layer. After exposure for theappropriate length of time, the exposed photoresist material isprocessed through developer and a post exposure bake. After thephotoresist has been processed the substrate is'then placed in a diluteacid etchant to etch the dark bismuth oxide in the appropriate processedregion of the photoresist. The proper etching time, combined with theproper photoresist spinning rate, exposure and development times willresult in a very sharp print. By over etching a silhouette type effectcan be obtained. Where a gold (or silver or platinum, etc.) layer hasbeen provided underneath or on top of the bismuth oxide, an increasedpost bake temperature diffuses the bismuth oxide into the gold and afteretching, the gold or gold coated substrate gives the effect of anantique gold color.

As illustrated in FIG. 2 the photoresist can optionally be first removedin a standard photoresist remover, or with the photoresist left on inplace the substrate and etched pattern are fired at appropriatetemperatures such as 150C (or higher) for at least 15 minutes forbakeout of the bismuth oxide. The bismuth oxide then adheres firmly tothe substrate.

As an added precaution, a plastic spray or glaze can be used, althoughwithout these extra coatings the bismuth oxide appears to be stable andpermanent. When glazes are used, firing temperatures should preferablybe under 250C and therefore the glazes used are basically soft glazes orsolder glazes.

It will be appreciated from the above description that it is relativelyeasy to print on both sides of a flat substrate or around a curvedsurface.

The method described above is very economical even on a one item basis,and where many identical items are desired, the same print is steppedand repeated on a large substrate and the substrate cut into smallerindividual pieces each with the desired picture.

It is believed that the invention has been described above in sufficientdetail to enable one skilled in the art to follow the method and producearticles in accordance with this invention. For further illustration,the following ex ample is given of one article made in accordance withthis invention.

A thin ceramic plate 99.5% pure alumina with a surface finish of 10microinches or better is first cleaned utilizing the following steps (a)hot trichloroethylene (TCE) degreaser for two minutes, (b) hot acetonefor five minutes, (c) boiling TCE for five minutes, (d) blown dry withnitrogen, (e) rinsed in de-ionized water, (f) blown dry with nitrogen,(g) hot nitric acid for five minutes, (h) rinsed in de-ionized water forten minutes, (i) blown dry with nitrogen, (j) hot isopropyl alcohol forfive minutes, and (k) blown dry with nitrogen. Clean substrates areloaded in a vacuum chamber evacuated to better than 2 X l0" torr andwherein bismuth trioxide positioned in alumina coated boat is evaporatedonto the substrates to a thickness of between 0.4 and 1 micron. Aphoto-resist coating of the KMER- type for a photonegative is spincoated on the substrate at a spinning speed of 2000 r.p.m. for thirtyseconds and prebaked in accordance with the instructions of themanufacturer, i.e., ll90F. for fifteen minutes for the KMER. Thesecoated substrates were wrapped in light-tight packages and hermeticallysealed. The picture was printed on the photo-resist material using a 500watt projector lamp for making a contact print. With photonegatives ofdifferent qualities, exposure times of from six seconds to one minutewere utilized. Next, the photo-resist was developed in accordance withthe manufacturer's instructions of one and onehalf minutes in developer,thirty seconds in rinse, ten to fifteen seconds in isopropyl alcohol andblown dry in nitrogen. The ceramic and developed photo-resist were postbaked at 350F. for fifteen minutes and cooled to room temperature. Thearticle was then etched and the bismuth oxide toned in dilute acidaccording to visual preference and using one part nitric acid to threeparts water for the etchant and one part nitric acid to five parts waterfor toning with the article thereafter washed in water and dried. Thefinal step was a bake out of the bismuth oxide and photo-resist in airat 400F. for thirty minutes in an oven.

Articles produced in accordance with this invention cannot only bedecorative jewelry and the like but can actually be projected as a slideif the substrate is translucent and mechanically strong. For example,ceramic 10 mils or less thick have been utilized to produce a black onwhite article as described above which can then be illuminated in astandard slide projector for projection of the image. Ceramics eventhicker can be utilized. Such utilization is illustrated in FIG. 5wherein a standard slide projector 31 is schematically shown andprovided with a correction mirror on the front thereof to correct thereversed image.

Ceramic slides of this type can withstand much higher temperatures thancan conventional slides. While the slide can even be as thick as 25mils, the thicker slide results in less image brightness.

While the invention has been described principally with respect to blackand white pictures, color pictures as decorative articles andphoto-slides can be produced. For example, the blue for die colorpicture can be achieved using cobalt.

We claim:

1. A method of making a decorative article comprismg evaporating a layerof image forming material of an oxide of bismuth for a resulting layerof bismuth trioxide of gray-black cubic crystalline form on a substrate,

coating the layered substrate with a photo sensitive material,

exposing the photo sensitive material with a picture,

developing the picture exposed photo sensitive mate rial and etchingaway the undesired bismuth trioxide of grayblack cubic crystalline formdefined by the picture thereby leaving the image forming bismuthtrioxide of gray-black cubic crystalline form on the substate.

2. The method of claim 1 wherein the layering step includes evaporatinga layer of image forming material of bismuth trioxide for a resultinglayer of bismuth trioxide of gray-black cubic crystalline form on analumina substrate.

3. The method of claim 1 wherein the layering step includes evaporatinga layer of image forming material of bismuth trioxide for a resultinglayer of bismuth trioxide of gray-black cubic crystalline form on ametal coating on an alumina substrate.

4. The method of claim 1 wherein the layering step includes evaporatinga layer of bismuth trioxide of yellow rhombic crystalline form on thesubstrate.

6 5. The method of claim 1 wherein the layering step includesevaporating a layer of bismuth trioxide of white rhombic crystallineform on the substrate.

6. A method of making a decorative article comprising the steps of:

evaporating a layer of image forming material of hismuth trioxide for aresulting layer of bismuth trioxide of gray-black cubic crystalline formfor a resulting color contrasting picture on a thin alumina substrate,coating the layered sheet with a photoresist material, preexposurebaking of the photoresist, photographically exposing the layeredsubstrate with a picture, developing the exposed photoresist, postexposure baking the photoresist, etching the undesired image formingbismuth trioxide layered on the alumina substrate and post etch bakingthe assembly. 7. The method of claim 6 wherein the layering stepincludes applying bismuth trioxide of a gray-black cubic crystallineform on a metal coating on the alumina substrate.

1. A METHOD OF MAKING A DECORATIVE ARTICLE COMPRISING EVAPORATING ALAYER OF IMAGE FORMING MATERIAL OF AN OXIDE OF BISMUTH FOR A RESULTINGLAYER OF BISMUTH TRIOXIDE OF GRAY-BLACK CUBIC CRYSTALLINE FORM ON ASUBSTRATE, COATING THE LAYERED SUBSTRATE WITH A PHOTO SENSITIVEMATERIAL, EXPOSING THE PHOTO SENSITIVE MATERIAL WITH A PICTURE,DEVELOPING THE PICTURE EXPOSED PHOTO SENSITIVE MATERIAL AND ETCHING AWAYTHE UNDESIRED BISMUTH TRIOXIDE OF GRAYBLACK CUBIC CRYSTALLINE FORMDEFINED BY THE PICTURE
 2. The method of claim 1 wherein the layeringstep includes evaporating a layer of image forming material of bismuthtrioxide for a resulting layer of bismuth trioxide of gray-black cubiccrystalline form on an alumina substrate.
 3. The method of claim 1wherein the layering step includes evaporating a layer of image formingmaterial of bismuth trioxide for a resulting layer of bismuth trioxideof gray-black cubic crystalline forM on a metal coating on an aluminasubstrate.
 4. The method of claim 1 wherein the layering step includesevaporating a layer of bismuth trioxide of yellow rhombic crystallineform on the substrate.
 5. The method of claim 1 wherein the layeringstep includes evaporating a layer of bismuth trioxide of white rhombiccrystalline form on the substrate.
 6. A method of making a decorativearticle comprising the steps of: evaporating a layer of image formingmaterial of bismuth trioxide for a resulting layer of bismuth trioxideof gray-black cubic crystalline form for a resulting color contrastingpicture on a thin alumina substrate, coating the layered sheet with aphotoresist material, preexposure baking of the photoresist,photographically exposing the layered substrate with a picture,developing the exposed photoresist, post exposure baking thephotoresist, etching the undesired image forming bismuth trioxidelayered on the alumina substrate and post etch baking the assembly. 7.The method of claim 6 wherein the layering step includes applyingbismuth trioxide of a gray-black cubic crystalline form on a metalcoating on the alumina substrate.